<template>
  <view>
    <!-- 自定义搜索组件 -->
    <my-search></my-search>
    <view class="scroll-view-container">
      <!-- 左滚动区域 -->
      <scroll-view class="left-scroll-view" scroll-y="true" :style="{height:wh+'px'}">
        <block v-for="(item,i) in catList" :key="i">
          <view :class="['left-scroll-view-item',i=== active?'active':'']" @click="changeActive(i)">{{item.cat_name}}
          </view>
        </block>
      </scroll-view>
      <!-- 右滚动区域 -->
      <scroll-view class="right-scroll-view" scroll-y="true" :style="{height : wh+'px'}" :scroll-top="scrollTop">
        <!-- 二级分类区域 -->
        <view class="cat-lvl2" v-for="(item2,i2) in catLevel2" :key="i2">
          <view class="cat-lvl2-title">/ {{item2.cat_name}} /</view>
          <!-- 三级分类区域 -->
          <view class="cat-lvl3">
            <view class="cat-lvl3-item" v-for="(item3,i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
              <image :src="item3.cat_icon"></image>
              <text>{{item3.cat_name}}</text>
            </view>
            
          </view>
        </view>
        
      </scroll-view>

    </view>


  </view>
</template>

<script>
  export default {
    data() {
      return {
        //当前窗口可用高度= 屏幕高度 - navigationBar高度 - tabBar 高度
        wh: 0,
        //分类列表数据
        catList: [],
        //二级分类列表数据
        catLevel2:[],
        //激活的样式
        active: 0,
        //设置滚动条距离顶部位置
        scrollTop:0,
      };
    },
    onLoad() {
      //获取当前系统信息
      const sysInfo = uni.getSystemInfoSync();
      //console.log(sysInfo);
      this.wh = sysInfo.windowHeight-50;
      this.getCatList();

    },
    methods: {
      async getCatList() {
        const {
          data
        } = await uni.$http.get('/api/public/v1/categories');
        //console.log(data);
        if (data.meta.status === 200) {
          this.catList = data.message;
          this.catLevel2=this.catList[0].children;
        } else {
          uni.$showMsg();
        }
      },
      changeActive(i){
        this.active=i;
        this.catLevel2=this.catList[i].children;
        //scrollTop前后不能一样,否则无法赋值
        this.scrollTop=this.scrollTop===0?1:0
      },
      gotoGoodsList(item3){
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?cid='+item3.cat_id
        })
      }
    }
  }
</script>

<style lang="scss">
  .scroll-view-container {
    display: flex;
  }
  .left-scroll-view {
    width: 120px;
    .left-scroll-view-item {
      line-height: 60px;
      background-color: #f7f7f7;
      text-align: center;
      font-size: 12px;
      &.active {
        background-color: #FFFFFF;
        position: relative;
  
        &::before {
          content: '';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          top: 50%;
          left: 0;
          transform: translateY(-50%);
        }
      }
    }
  }
  .right-scroll-view{
    .cat-lvl2-title{
      font-size: 12px;
      padding: 15px 0;
      text-align: center;
      font-weight: blod;
    }
    .cat-lvl3{
      display: flex;
      flex-wrap: wrap;
      .cat-lvl3-item{
        width: 33.33%;
        display: flex;
        flex-direction: column;
        align-items: center;
        margin-bottom: 10px;
        image{
          width: 60px;
          height: 60px;
        }
        text{
          font-size: 12px;
          
        }
        
      }
    }
    
  }
</style>
